1. Field of the Invention
This invention pertains to heat transfer fluid cycling. More particularly this invention pertains to an apparatus and method for cleaning heat transfer fluid in an HVAC system.
2. DESCRIPTION OF THE PRIOR ART
Heating, ventilating and air conditioning (HVAC) systems commonly utilize closed loop systems for pumping heat transfer fluid throughout a building. In such a closed loop system, a central air conditioner or boiler forces heat transfer fluid through piping which is then returned to the air conditioner/boiler. In such systems, glycol is a primary component of the fluid.
After continued use, the heat transfer fluid becomes contaminated with particulate matter or other contaminants. Also, the glycol can break down losing its usefulness and presenting a maintenance hazard to the pipes. As a result, it has become necessary to add glycol to a system and, from time to time, to clean the heat transfer fluid contained within the HVAC system. By cleansing the heat transfer fluid, corrosion and related maintenance problems can be reduced. Also, a clean HVAC system reduces a danger of biological contamination and may even cut power costs.
In industrial applications (e.g., a school), an HVAC system may contain as much as 10,000 gallons of heat transfer fluid. Prior art techniques for cleansing a heat transfer fluid within a system would include simply removing the old heat transfer fluid and disposing it. New heat transfer fluid is then substituted into the system. However, such disposal is environmentally unacceptable. Alternatively, the heat transfer fluid can be drained from the system and cleansed. However, due to the large volume of heat transfer fluid in an HVAC system, this procedure is not commonly practical. Also, if the system is drained, air pockets can result in the piping when fluid is readmitted.
It is an object of the present invention to provide an apparatus and method for cleansing glycol containing heat transfer fluid within an HVAC system without interruption of the systems normal operation.